1. Field of the Invention
The present invention relates generally to medical devices and methods. More particularly, the present invention relates to medical devices that carry multiplexed effectors for performing a variety of diagnostic and therapeutic procedures.
Intravascular and intraluminal interventions and monitoring have become essential in modern cardiology and other medical fields. Of particular interest to the present invention, a variety of intravascular catheters, implantable sensors, implantable stimulation leads, and other devices have been developed for monitoring and affecting cardiac performance and other patient parameters. While enjoying significant utility, such monitoring and therapeutic catheters have generally included only a single or limited number of sensors and/or actuators (together referred to generally herein as “effectors”). Thus, the ability to monitor or affect multiple parameters and/or a single parameter at a number of distributed positions along the catheter or other device has been significantly limited. One of the main reasons why catheters and other devices have only included a limited number of effectors has been the requirement to “hard wire” each effector to a dedicated connection or other terminal on the catheter.
Therefore, it would be desirable to provide improved catheters, implantable stimulation leads, and other devices for the intravascular and intraluminal monitoring of patient parameters, such as pressure, temperature, conductivity, electrical potential, blood flow, blood volume and the like. It would also be desirable to provide improved catheters and other devices for intravascular and intraluminal delivery of therapeutic interventions, such as tissue ablation and electrical stimulation for cardiac pacing and other physiologic purposes. It would be particularly desirable to provide such devices with multiple effectors (sensors and/or actuators) distributed over the product. It would be further desirable to permit a single device to include effectors of many different types and to permit communication to and from the effectors using a limited number of wires in the devices. It would be further desirable to provide convenient fabrication methods for such devices and convenient methods for using such devices in patients. At least some of these objectives will be met by the inventions described below.
2. Description of the Background Art
Catheters having multiple electrodes for cardiac mapping, ablation and/or other purposes are shown in U.S. Pat. Nos. 4,397,314; 4,603,705; 4,776,334; 4,815,472; 4,881,410; 5,113,868; 5,419,767; 5,509,411; 5,579,764; 5,591,142; 5,662,587; 5,924,997; 5,902,248; 6,033,398; 6,309,385; and published applications U.S. 2002/0156417 A1 and U.S. 2002/0026183 A1. U.S. Pat. No. 4,815,472 describes a catheter having multiple solid state sensors permanently bonded to two common leads with multiplexing capability. U.S. Pat. No. 5,579,764 describes a mapping and ablation catheter having a common bus without multiplexing. U.S. Pat. No. 2002/0156417 describes MEMS sensing modules with conditioning circuitry connected to a dual-lead bus in the catheter.